In a mobile communication system, it is possible for multiple mobile terminals to perform radio communication with a base station using the same frequency.
When the base station performs radio communication with a certain mobile terminal, the quality of reception deteriorates if a received signal (desired signal) which is received from the mobile terminal is interfered with by a received signal (interfering signal) which is received from another mobile terminal.
As an example of an interference cancellation technique for canceling such an interfering signal, there is a technique in which an antenna is constituted by multiple antenna elements, and the received signals of the antenna elements are antenna-combined to control the directivity of the antenna (see Patent Literature 1). According to this, it is possible to cancel an interfering signal by controlling the directivity of the antenna so that a null is formed in the direction of the interfering signal.